Monocoque

Deperdussin Monocoque, with wooden shell construction

Monocoque (/ˈmɒnəkɒk, -kk/ MON-ə-ko(h)k), also called structural skin, is a structural system in which loads are supported by an object's external skin, in a manner similar to an egg shell. The word monocoque is a French term for "single shell".[1]

First used for boats,[2] a true monocoque carries both tensile and compressive forces within the skin and can be recognised by the absence of a load-carrying internal frame. Few metal aircraft other than those with milled skins can strictly be regarded as pure monocoques, as they use a metal shell or sheeting reinforced with frames riveted to the skin, but most wooden aircraft are described as monocoques, even though they also incorporate frames.

By contrast, a semi-monocoque is a hybrid combining a tensile stressed skin and a compressive structure made up of longerons and ribs or frames.[3] Other semi-monocoques, not to be confused with true monocoques, include vehicle unibodies, which tend to be composites, and inflatable shells or balloon tanks, both of which are pressure stabilised.

  1. ^ Merriam-Webster Dictionary, 2011
  2. ^ Garson, Paul (May–June 2018). "Art Deco on Wheels: 1930 Majestic". Motorcycle Classics. Retrieved October 6, 2018.
  3. ^ Airframe and Powerplant Mechanics Airframe Handbook (Publication AC65-15A). Washington, DC: US Department of Transportation Federal Aviation Administration Standards Division. 1976. p. 4. ISBN 0-16-036209-1.